A non-reciprocal circuit device such as an isolator or a circulator is used in, e.g., a mobile communication device such as a mobile phone or a wireless device, or a communication device utilized in a base station of such a mobile communication device.
This type of non-reciprocal circuit device is configured to accommodate an assembly including a permanent magnet, a magnetic pole plate, and a gyromagnetic component in a magnetic metal holder which functions as a yoke.
Meanwhile, in recent years, in this type of non-reciprocal circuit device, a reduction in height is an important technical problem in order to cope with a demand for a reduction in size and weight of a mobile communication device.
Further, in this type of non-reciprocal element, there arises a concern over reliability when a stress, reheating or the like is applied to a terminal substrate by reworking and others, which results in a problem of an apprehension about recycling of a product and a problem of generation of a yield loss. In order to solve these problems, it is important for the non-reciprocal circuit device to have a configuration with a high mechanical securing strength.
Furthermore, in terms of cost reduction, important points are a reduction in the number of components, a improvement in the yield of assembly, a decrease in the number of assembling steps and a low assembly cost.
Moreover, it is preferable for the non-reciprocal circuit device to include a configuration in which a layout can be readily changed when any other additional circuit must be installed by any method. In particular, in case of developing a variation having a receptacle configuration, it is important to avoid an increase in a manufacturing cost.
Various configurations about this type of non-reciprocal circuit device have been conventionally proposed. As concrete typical examples, Patent References 1 to 4 can be cited.
However, it cannot be said that Patent References 1 to 4 can sufficiently solve the above-described problems.
Patent Reference 1: JP 2003-124,711A
Patent Reference 2: JP H10-294,606A
Patent Reference 3: JP 3,399,099B2
Patent Reference 4: U.S. Pat. No. 6,337,607B1